Difference Between Sea vs Lake
It is no longer news that over seventy percent of the earth’s surface is covered by water. These water bodies come in different shapes and sizes and can be seen all over the world. Water is classified into four types: surface, waste, ground, and stormwater.
For the sake of this post, we will focus on surface water, specifically the difference between lake and sea. The former is a large expanse of water surrounded by land, while the latter is a much larger expanse of water surrounding different land masses. As important as these definitions may be, there are still a lot more to these bodies of water that we will share with you.
Definition of Sea
A sea is defined as a salty water body that is partly surrounded by land. It could be anywhere between moderate to very large in size. The largest measures over 3.8 million square km.
There are special features that make this type of body of water stand out. First, it is salty, which is why it is called salt water in the first place. Also, it contains gases and small amounts of other dissolved substances and particles of elements like gold, iron, copper, calcium, silver, and so on.
These impurities form the basis of the reason why it is not advisable to drink water from the sea. According to health experts, the salt level is too high for the body, and the kidneys can only make urine that is less salty than seawater. So, you would have to drink fresh water to help dilute the seawater, or you would become dehydrated.
Definition of Lake
A lake is simply defined as fresh water surrounded by land. Lakes are not as large as seas. The smallest lakes are quite small. Ironically, the largest lake has the word “sea” in its name. The Caspian Sea measures over 385,000 square km. Interestingly, many people refer to the Caspian Sea as a sea because it is so large, but considering certain features, it is nothing but a really large lake.
The most interesting feature that shows the difference between sea and lake is that the former contains some salt while the latter does not. Since it does not contain salt, this type of water body provides a habitable ecosystem for fish, wildlife, and other aquatic creatures. It also serves as a recreational spot for people and can even be a popular tourist site.
According to history, lakes tend to age over time. Since they are exposed to the atmosphere, they will collect some deposits over time, causing them to become shallower.
However, the process can take as long as thousands of years before a lake starts showing signs of aging. If there is a heavy human influence, it may take less time than that, but whatever the case, a lake does not become shallow overnight under normal circumstances.
Main Differences Between Sea vs Lake
There are numerous factors you need to consider in the sea vs lake comparison if you wish to understand how they are different from each other. The table below shows these differences in terms of definition, structure, size, and so on.
| Basis of Comparison | Sea | Lake |
| Definition | A body of salt water that is partly surrounded by land | Fresh water surrounded by land |
| Size | Bigger than a lake and smaller than an ocean | Smaller than seas |
| Content | Salt water | Fresh water |
| Existence | More or less permanent | Formed, matures, and dies after a while and is considered temporal in the geological time scale |
| Ecosystem | It harbors a large variety of aquatic creatures that are mostly large in size. Examples include whales, giant squids, octopuses, etc. | Lakes harbor small aquatic creatures like ducks, fish, etc. |
Difference Between Sea and Lake: Conclusion
In conclusion, the lake vs sea comparison reveals some differences in size, existence, geological scale, and a lot more. While these two may be a little confusing and hard to tell apart, knowing these differences will help you differentiate them.
The main difference between these two can be seen in which contains or does not contain salt. The type of creatures that live in them also helps to distinguish between them.
